Re: [PATCH v5] pseries: prevent free CPU ids to be reused on another node

From: Laurent Dufour
Date: Tue Aug 03 2021 - 13:38:14 EST


Le 03/08/2021 à 18:54, Nathan Lynch a écrit :
Laurent Dufour <ldufour@xxxxxxxxxxxxx> writes:
V5:
- Rework code structure
- Reintroduce the capability to reuse other node's ids.

OK. While I preferred v4, where we would fail an add rather than allow
CPU IDs to appear to "travel" between nodes, this change is a net
improvement.

Reviewed-by: Nathan Lynch <nathanl@xxxxxxxxxxxxx>


Thanks Nathan,

Regarding the reuse of other nodes free CPU ids, with this patch the kernel does it best to prevent that. Instead of failing adding new CPUs, I think it's better to reuse free CPU ids of other nodes, otherwise, only a reboot would allow the CPU adding operation to succeed.

Laurent.